Abstract

An experimenkal investigation has been conducted at M=6 to determine the effect of cooling on the near wake of13; a two-dimensional circular cylinder. Mean flow properties13; were determined from Pitot pressure, static pressure, and13; hot-wire recovery temperature measurements as free stream13; Reynolds number of 0.905 x lo4 and 2.95 x 10 for both batic and cooled models, the later at about two tenths of13; the free stream stagnation temperature. The near wake was13; laminar for adiabatic model at both the Reynolds numbers13; and for the cold model at the lower Reynolds number. Transition was apparent in the near wake of the cold model at the higher Reynolds number. The base pressure decreased with cooling. The wake shocks, the shear layer edges and the thermal layer edges moved closer to the wake centerline13; with cooling and with increase in Reynolds number. In the13; recirculating region, the transverse total temperature distributions exhibited a minimum close to the dividing stream line for all the cases, and the total temperature on the centerline was nearly constant and equal to the value at the rear stagnation point indicating that the heat transfer in this region was mainly by convection. The existence of a thin thermal layer on the base was evident for the cold models.